1. Field of the Invention
The present invention relates to an air cleaner using an ionic wind.
2. Description of the Prior Art
It is well known in the art that a corona discharge occurs from a discharge electrode such as a needle electrode to a counter electrode such as a plate electrode when a high voltage is applied between the discharge and counter electrodes, and that an ionic wind is then generated.
In this specification, the term "ionic wind" is used to refer to the phenomenon in which air in the vicinity of the discharge electrode is ionized by the corona discharge from the discharge electrode, and ions are moved by an electrostatic force toward the counter electrode. During motion of the ions, a number of neutral molecules are scattered to produce a molecular flow, i.e., a wind. The ionic wind has a velocity of several meters per second, and the force of the wind can be increased or decreased according to the required application of the air cleaner.
When the corona discharge occurs, dust in the air is also ionized, and this ionized dust can be collected on the counter electrode, thereby providing an electrostatic dust collecting function. In this specification, the term "dust" is used to refer mainly to the particulate pollutants such as cigarette smoke.
A plurality of parallel plate electrodes act as a dust collecting electrode member and are arranged at given intervals downstream of the counter electrode. The dust collecting electrode member is arranged in such a manner that the proper electric field is established between every two adjacent electrodes so as to collect dust.
However, a high voltage source is required to generate an ionic wind, and another high voltage source is required for generating the dust collecting electric field. Thus, two high voltage sources are required: one for generating an ionic wind; and the other for collecting the ionized dust. Therefore, in the prior art, an ionic wind type air cleaner which aims at a compact construction has disadvantages in space and cost.